Wireless networks have experienced increased development in the past decade. One of the most rapidly developing areas is mobile ad hoc networks (MANETs). Physically, a MANET includes a number of geographically distributed, potentially mobile nodes sharing one or more common radio channels. Compared with other types of networks, such as, cellular networks or satellite networks, the most distinctive feature of MANETS is the lack of any fixed infrastructure. The network is formed of mobile (and potentially stationary) nodes, and is created on the fly as the nodes communicate with each other. The network does not depend on a particular node and dynamically adjusts as some nodes join or others leave the network.
An improvement in MANETs is disclosed in U.S. Pat. No. 7,216,282 to Cain, assigned to the present application's assignee. Cain discloses a MANET that may include a source node, a destination node, and a plurality of intermediate nodes. The source node may establish a plurality of routes to the destination node for transferring data therebetween, where each route passes through at least one of the intermediate nodes. The source node may also encode a plurality of data packets using a forward error correction (FEC) encoding algorithm to generate error correction data for the data packets, interleave the data packets and error correction data, and distribute and send the interleaved data packets and error correction data across the routes to the destination node. Furthermore, the destination node may receive and deinterleave the interleaved data packets and error correction data. The destination node may also decode the data packets based upon the error correction data using an FEC decoding algorithm to correct compromised data packets.
Another improvement in MANETs is disclosed in U.S. Pat. No. 7,085,290 to Cain et al., also assigned to the present application's assignee. Cain et al. discloses a MANET that may include a plurality of mobile nodes, each including a wireless communications device and a controller connected thereto. At an upper protocol layer, the controller may establish a quality-of-service (QoS) threshold. At an intermediate protocol layer, the controller may select at least one route for transmitting data to at least one destination mobile node based upon the QoS threshold, and determine whether a QoS metric for the selected route falls below the threshold. At a lower protocol layer, the controller may cooperate with the wireless communications device to transmit data to the at least one destination mobile node via the at least one selected route, and cooperate with the wireless communications device at the lower protocol layer to adjust signal transmission power, pattern, and/or gain based upon a determination that the QoS metric has fallen below the QoS threshold.
A typical communications system may sometimes include an approach to scheduling communications between a transmitter device and a receiver device, i.e. a isosynchronous communications system rather than an asynchronous communications system. The isosynchronous communications system, for example, a voice over Internet Protocol (VoIP) system, transmits data for delay sensitive applications. Advantageously, isosynchronous communications systems provide for continuous synchronous transmission of bits. The transmission is divided into samples, each sample being encapsulated in a packet payload. The delay between each sample may be tolerated depending on the communications system. QoS demands in the isosynchronous communications system may be dependent on low latency high quality connections. Indeed, in typical VoIP protocols, for example, the Session Initiation Protocol and the H.323 protocol, a central server is used to manage the communications therebetween. Because of the infrastructureless and temporary nature of MANETs, isosynchronous communications, more particularly, VoIP, in MANETs may be problematic.